Hi S. -
Yes, I think it's very normal to feel a little blue about your daughter weaning herself. You may also be feeling a bit inadequate, but please don't. One mom was very correct in pointing out that some mothers have a hard time weaning THEMSELVES from the breastfeeding process, which unfortunately limits a lot of their children's independence.
It's pretty normal to feel blue in general after you've had a baby. That being said, cuddle with your daughter as much as you can. Take little naps with her and give her lots of love, which she'll return to you ten-fold as she gets older. My kids were only breastfed, and mostly through pumping, for just a few months. Thankfully, their health didn't suffer, and they're very affectionate young people because my husband and I shower them with hugs and kisses everyday. Pure, unsolicited affection from your kids is the best kind of therapy for the mama blues. :) Blessings to you and yours.